Added Achievement and Statistics

By: Dinnerbone <dinnerbone@dinnerbone.com>

paper-api/src/main/java/org/bukkit/Achievement.java

@@ -0,0 +1,67 @@
+
+package org.bukkit;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Represents an achievement, which may be given to players
+ */
+public enum Achievement {
+    OPEN_INVENTORY(0),
+    MINE_WOOD(1),
+    BUILD_WORKBENCH(2),
+    BUILD_PICKAXE(3),
+    BUILD_FURNACE(4),
+    ACQUIRE_IRON(5),
+    BUILD_HOE(6),
+    MAKE_BREAD(7),
+    BAKE_CAKE(8),
+    BUILD_BETTER_PICKAXE(9),
+    COOK_FISH(10),
+    ON_A_RAIL(11),
+    BUILD_SWORD(12),
+    KILL_ENEMY(13),
+    KILL_COW(14),
+    FLY_PIG(15);
+
+    /**
+     * The offset used to distinguish Achievements and Statistics
+     */
+    public final static int STATISTIC_OFFSET = 5242880;
+    private final static Map<Integer, Achievement> achievements = new HashMap<Integer, Achievement>();
+    private final int id;
+    
+    private Achievement(int id) {
+       this.id = STATISTIC_OFFSET + id;
+    }
+
+    /**
+     * Gets the ID for this achievement.
+     *
+     * Note that this is offset using {@link #STATISTIC_OFFSET}
+     *
+     * @return ID of this achievement
+     */
+    public int getId() {
+        return id;
+    }
+
+    /**
+     * Gets the achievement associated with the given ID.
+     *
+     * Note that the ID must already be offset using {@link #STATISTIC_OFFSET}
+     *
+     * @param id ID of the achievement to return
+     * @return Achievement with the given ID
+     */
+    public static Achievement getAchievement(int id) {
+        return achievements.get(id);
+    }
+
+    static {
+        for (Achievement ach : values()) {
+            achievements.put(ach.getId(), ach);
+        }
+    }
+}